Mooney M20J N9201R accident near Kansas City, Missouri

Probable cause

The pilot's improper decision to attempt continued flight after a momentary loss of engine power with usable runway remaining. Contributing to the accident were the pilot's premature retraction of the landing gear, the loss of engine power due to fuel system water contamination, and the pilot's failure to detect the fuel contamination during the preflight inspection.

NTSB analysis

**This report was modified on 1/5/2015. Please see the public docket for this accident to view the original report. **

The airplane experienced a total loss of engine power during takeoff from a runway that had a usable length of 6,827 feet; however, the pilot initiated the takeoff from a taxiway intersection, which left only about 5,313 feet of runway remaining. After the loss of engine power, the airplane descended to about 10 feet above ground level (agl) with the landing gear retracted; about half of the runway length remained. Engine power was restored, and the airplane subsequently climbed to between about 300 and 400 agl. The engine again lost power, and the airplane subsequently stalled and impacted a field. The landing gear remained retracted. Typically, the landing gear should be retracted after liftoff when the airplane has reached an altitude where, in the event of an engine failure or other emergency requiring an aborted takeoff, the airplane could no longer be landed on the runway.

The airplane arrived at the departure airport 3 days before the accident and was parked on the ramp. There was a trace of precipitation at the airport on the day of arrival and no precipitation on subsequent days. Examination of the airplane revealed the presence of water in the fuel diaphragm and fuel servo. No evidence of fuel contamination in the fuel pumps was found, and no reports of fuel contamination or engine power loss of airplanes that had been refueled from the fuel pumps before and after the accident were made.

Examination of the fuel filler caps revealed that the cap components were in place and that both caps were in place and secure. When water was poured onto the fuel caps when they were placed and secured back into position, they exhibited leakage into the fuel tank; however, the extent of deformation around the filler neck due to accident damage was unknown. During the most recent annual inspection, it was noted that the fuel cap O-rings were replaced because of water contamination of the fuel system. No record was found indicating that maintenance personnel pressurized the fuel tanks to check for fuel cap leakage in accordance with the airplane manufacturer's maintenance instructions. No internal obstruction was noted in the fuel system that would have precluded the pilot from detecting water in the system while sumping it during the preflight inspection.

Text from the NTSB. Open the NTSB docket for CEN13FA496 for the full record.